<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		
		<script>
			"use strict"
			
			// 创建symbol属性值
			let symbol = Symbol()
			console.log(symbol)
			let obj = {username: "kobe", age: 21}
			obj[symbol] ="hello"
			console.log(obj)
			
			let symbol2 = Symbol("one")
			let symbol3 = Symbol("two")
			console.log(symbol2 == symbol3)
			console.log(symbol2, symbol3)
			
			console.log("for in 遍历对象obj中的属性:")
			for(let i in obj){
				console.log(i)
			}
			
			// 可以定义常量
			const Person_key = Symbol("person_key")
			console.log(Person_key)
			
		</script>
	</body>
</html>
